Underreamer



G. C. DEAKINS UNDERREAMER Filed Deo. 6, 1927 2 Sheets-Sheet l [NVE/V701@ @v4/ef C'. Dea hs,-

June 30, 1931.

June 30, 1931. G. c. DEAKINS UNDERHEAMEH Filed Deo. 6. 1927 2 Sheets-Sheei 2 AIJITIII l Patented June 30, 1931 UNITED STATES PATENT OFFICE GROVE-R C. DEAKINS, OF ANAHEIIVL CALIFORNIA, .ASSIGNOR1 BY MESNE ASSIGNMENTS, TO JOHN GRANT, OF LOS ANGELES, CALIFORNIA UNDERREAMER Application led December 6, 1927. Serial No.'238,016.

This invention relates to apparatus for drilling wells and relates particularly to an improved form of underreamer which is adapted to be lowered through the casing of the well and to expand as it leaves the lower end of the casing so that it will underream the hole to a larger diameter than the well casing. Y

To explain the advantages of my invention, a brief description of the well drilling art will be given. It is common practice to drill a well by means of a bit secured to the lower end of a drill pipe, this drill pipe being rotated and lowered by mechanism of the derrick of the well. Although itY is usually'pra-ctice to drill a we'll without the use of casing, it is sometimes desirable to suspend a casing, through which the drill pipe extends, into the hole and lower'it as drilling progresses. When a casing is carried in this manner it is necessary that the hole being formed below the Casing be of larger diameter than the external diameter of the casing so that it may be lowered. The bit which is used todrill the hole below the casing is necessarily smaller in diameter than the casing because it must be lowered to the bottom of the well through t-he casing. It is the usual practice to attach an eX- pansible underreamer to the drill pipe directly above the bit. This expansible underreamer when Yit passes from the lower end of the casin g will expand into underreaming position and will underream the hole produced by the bit,' so that the easing may be I lowered. The common type of underreamer underre-amers.

is of such an involved construction that the parts thereof 'can be sufiiciently strong to resist the strains only in t-he large size of All of the underreamers with which the inventor is familiar cannot be made in a. size less than siX inches because of the fact that the parts of a size smaller than this will be so weak that it is dangerous to lower such an underreamer into a well.

In the present invention this disadvantage of present underreamers is overcome by producing an underreamer which is of extremely simple construction and which permits the parts to be made amply strong.

It is an object of the invention to provide an underreamer in which one end of the unde-rreaming element will be moved upward and swung outward when the underreamer passesfrom the lower end'of the casing.

Other objects and advantages of the inventioirwill be made to appear 1n the following description. i

The inventioir may be best understood by reference to the accompanying drawings in which: l

Fig. 1-is a diagrammatic View illustrating the invention.

Fig. 2 isa vertical section of the preferred form of the invention, 'the reaming elements being in extended position.

Fig. 3 is a section.` similar to Fig. 2, the reaming elements being in retracted position.

Fig. 4 is a section taken on the line 4;- 4 of Fig. 2. f z

Fig. 5 is a section taken on the line of Fig. 2.

Fig. 6 is an elevational view of a second form of the invention.

Fig. 7 is a section taken on the line 7.-7 of Fig. 6. f,

Referring particularlyto Fig. 1, the numeral 11 represents a well which is being drilled by a bit 12. The bit 12 is mounted on the lower end of a drill pipe 13, this drill pipe 13 being rotated at the surface of the ground by a rotary machine 14. Secured in the drill column 13 above the bit 12 is an underreamer 17 embodying the features of the invention. The purpose of the underreamer 17, as illustrated in Fig. 1, is to ream the hole being drilled by the bit 12 to such a size that the casing 18 being carried may be moved downward as the well is deepened.

Referring particularly to Figs. 2 to 5 inelusive, the details of one form of my inv lare formed from the lower edge thereof.

i These cavities 27 are spaced 120 apart and are the same radial distances from the axis of the body. The cavities 27 are provided with inner inclined faces 28 which slope upward and outward into a top pocket .29 of each cavity 27. The lower flange 25 is pro# vided with vertical openings 30 which are arranged directly below the inner parts of the cavities 27.

The invention provides cutter supports in the form of cutter shafts 34. The upper ends 35 of the cutter shafts are adapted to rest in the cavities 27 and the lower ends 36 are adapted to rest in the openings 30. Carried by each cutter shaft 34 is a reaming or cutting element 37 which may rest on an annular shoulder 38 of each of the cutter shafts 34.

Located in the openings 30 are springs 39. The upper ends of the springs 39 engage the lower ends 36 of the cutter shafts 34 sur rounding the central projections 41 thereof. The lower ends of the springs 39 engage closure buttons 43 surrounding the central projections 44 thereof. The closure buttons 43 are held in place by means of a plate 45 which is screwed onto a threaded portion 46 of the bod 21, which threaded portion 46 is located irectly below the lower flange 25. n From an inspection of Figs. 2 and 3, it will beseen that the springs 39 press upward on the cutter shafts 34 and tend to resiliently retain them inthe position shown in Fig. 2. The cutter shafts 34 will occupy ositions as illustrated in Fig. 3 only when t ey are retainedfin these positions against the action of the springs 39. The motion of the cutter shafts 34 in moving from the position shown in Fig. 3 into the position shown in Fig. 2 is important to the invention because it makes possible a simple desi n, and a simple design permits the parts to made of rigid construction. A further advantage accruing Afrom the motion of the cutter shaft is that.

a maximum expansion is possible. As each cutter shaft is moved upward by the action of the s ring 39 acting against it, the lower end 36 will move substantially parallel to the axis of the body 21. The upper end 35 being in en agement with the inclined face 28 is guided outward until the upper end arrives at the pocket 29. 1t will be seen that the cutter s aft 34 as it moves upward is swun about a point located within the lower end 36, the upper end thereof moving outward.

When the underreamer is used in the aparatus shown in Fig. 1, the parts are moved into retracted position, as shown in Fig. 3,

lagainst the action of the springs 39. The

parts arethen held in this position by any suitable means such as tying a rope or wire around the cutter elements' 37. The assembly is then lowered into the well 11 by means of the drill pipe 13. The wire or rope holding the underreamer in retracted position is soon broken due to its contact with the well casing 18. The parts then expand so that the cut ter elements 37 engage the inner surface of the casing 18. When the underreamer emerges from the .lower end of the casing 18 the `springs 39 force the cutter shafts 34 upward -invention the construction is substantially the same except that in place of using separate springs 39 for each of the cutter shafts 34, a single spring is provided. Referring particularly to Flg. 6, the lower ends 36 of the shafts 34 extend entirely through the openings 30. The body 21 is provided with a long cylindrical portion 55 below the lower flange 25. The upper part of the cylindrical portion 55 is provided with keys 56. Placed on the lower part of the cylindrical portion 55 is a sleeve 57. Screwed onto a lower threaded portion 58 is a nut 59 which engages the sleeve 57 and clamps it in place, the upper end of this sleeve being adapted to engage the lower ends of the keys 56; An loperating plate 60 surrounds the upper part of the cylindrical portion 55 and is prevented from rotating by means of the keys 56. The lowest position of the operating plate 60 is determined by the upper end of the sleeve 57 which provides an engaging shoulder 61. The lower ends 36 of the cutter shafts 34 rest in sockets 62 of the operating plate 60.- Compressed between the operating plate 60 and the nut 59 is a spring 64. The spring 64 exerts a resilient upward pressure on the operating plate 60 which in turn presses on the cutter shafts v34, tending to move them from retracted into extended positions.

The operation of this form of the invention is identical with that of the first form of the invention. The main difference is in the construction of the means for moving the cutter shafts from retracted into extended positions.

From the foregoing description it will be seenfgthat the underreamer of this invention is offvery simple construction and that the parts 'are of rigid design. One very important part ofthe invention is the manner in which the cutter shafts move from retracted into extended positions. It is a very important part of the invention to provide the cav ities 27 which swing the upper ends of.

the cutter shafts 34 outward as they are moved upward. l L

I claim as my invention:

1. An underreamer comprising: a body; flanges formed on said body; an extension extending from said body; a member slidable on said extension; a cutter support carried by-said body, one end of said cutter support engaging an inclined face in one of said flanges and having'an opposite end portion passing through the other of said flanges, said cutter support having a retracted and extended position, the end of said cutter support being swung outward by said inclined face when it is inoved into extended position, and the opposite end of said cutter support being supported by said slidable member so as to move substantially parallel tothe axis of said body; means for actuating said slidable member to move said cutter support from retracted to extended position; and a cutter carried by `said cutter support.

2. An underreamer comprising: a body having spaced flanges and an extension extending therefrom; a member slidably mounted on said extension; a cutter support carried by said body, one end of said cutter support engaging an inclined face in one of said flanges, said cutter support having a retracted and extended position, the end of l said cutter support being swung outward by said inclined face when it is moved into extended position, and the opposite end of said cutter support being supported by said slidable member so as to move substantially parallel to the axis of said body; guide meansfor guiding said cutter support; means carried by said extension and adapted for engagement with said slidable member for moving said cutter support from retracted to extended position; and a cutter carried by said cutter slpport.

3. n underreamer comprising: a body; flanges on said body; an extension on said body; a member slidably mounted on said extension; a cutter support carried by said body, one end of said cutter support being supported by said slidable member and the opposite end engaging an inclined face in one of said flanges, said cutter support having a retracted and extended position, the upper end of said cutter support being swung outward by said inclined face when it is moved into extended position and the supported end of said cutter support being adapted to move substantially parallel to the axis of said body, said cutter support extending through an opening in the other of said flanges for guiding the same; a nut having threaded engagement with said extension; a spring disposed on said extension between said nut and said slidable member and adapted for engagetending therefrom; a member slidable on said extension; a cutter support having one end mounted in said slidable member and the opposite end engaging an inclined face of one of'said flanges, said cutter support having a retracted and extended position, one end of said cutter support being swung outward by said inclined flange face when it is moved into extended position, said cutter support extending through an openin in the other of said flanges so as to move su stantially parallel to the axis of said body; a nut threaded on said extension; a sleeve mounted on said extension; a spring surrounding said sleeve and engaging said slidable member to move said cutter support into extended position; and a cutter carried by said cutter support.

5. An underreamer as set forth in claim 4 wherein the body is constructed as a unit.

6. An underreamer as set forth in claim 4 wherein the movement of the slidable member may be regulated.

7. An underreamer com rising: al body; flanges formed on said b y; a cutter support movably mounted in said flanges so as to be capable of being swung outward when it is moved into extended position; an ex` tension on said body; a plate slidably mounted on said extension, one end of said cutter support engaging an inclined face of one of said flanges, and the opposite end of said cutter support being carried by said plate so as to movesubstantially parallel to the axis of said body; a sleeve on .said extension; a spring surrounding saidfsleeve and adapted forengagement with said plate to move said fjlanges; an operating plate slidably mounted on said extension, said plate supporting said cutter su port; a spring on said extension adapted or engagement with said operating plate for moving said cutter support into an extended position; and a cutter carried by said cutter support.

9. In an expansive underreamer, the combination of a body having a cam surface formed in its upper portion, a substantial vertical cutter bearing rod associated with IOL' said body, a roller cutter mounted longitudinally on said rod rotatable with said vertical rod as its axis, the upper end of said rod bearing on said cam surface, guide means on said body below the cutters to guide the lower end of said rod, an expander associated with said body below said guide means, said lower end of said rod resting on and having substantial pivotal movement with respect to said expander', resilient means below said expander pressing downwardly against said body and upwardly against said expander to move said rod and cutters upwardly, said upper cam surface directing said upper end of said rod to move outwardly and upwardly during this movement the lower end of said rod moving upward in a vertical direction and pivoting whereby the cutters are expanded.

10. In an expansive reamer, the combination of a body, a vertically extending cutter element associated with the body and comprising a roller on a vertically extending axis, mounting means for the lower end of the cutter element allowing vertical movement and lateral tilting movement ot the element, and coacting means on the body and upper end of the cutter element to cause outward tilting movement ot the upper end of the element by virtue of upward movement thereof, said last mentioned means comprising a vertically extending pin and a recess, one of which is provided with a diagonally extending expanding surface.

11. In an Iexpansive reamer, the combination of a body, a vertically extending cutter clement associated with the body and comprising a roller on avertically extending axis, mounting means for the lower end of the cutter element allowing vertical movement and lateral tilting movement of the element, and coacting means on the body and upper end of the cutter element to cause outward tilting movement of the upper end of the element by virtue Vof upward movement thereof, said last mentioned means comprising a vertically extending pin and a recess, one of which is substantially coaxial with the roller and one of which is provided with a diagonally extending expanding surface.

12. In an expansive reamer, the combination of a body having cam surfaces at its upper ends; a cutter rod extending axially of the body and supported thereon for longitudinal movement in relation to said body, a roller cutter on said rod rotatable with said rod as its axis and extending substantially vertical, the upper end of said rod bearing on said caml surface; mounting means upon which the lower end of said rod is loosely seated allowing longitudinal and pivotal movement of said rod to enable tilting movement ofthe latter at its upper end including vresilient means pressing said rod upwardly in relation to said body, said cam surface directing the upper end of said rod outwardly and upwardly whereby said rod is tilted outwardly to expanded position.

13. In an expansive reamer, the combination of a body having a cam surface at its upper end and a rod retaining wall; a cutter rod extending axially of the body and supported thereon for longitudinal movement in relation to said body, a roller cutter on said rod rotatable with said rod as its axis and extending substantially vertical, the upper end of said carrier bearing on said cam surface; mounting means upon which the lower end ot said rod is loosely seated allowing longitudinal and pivoted movement of said rod to enable tilting movement of the latter at its upper end including resilient means pressing said rod upwardly in relation to said body, said cam surface directing the upper end of said rod outwardly, upwardly and against said retaining wall whereby said rod is tilted outwardly to expanded position and held against outward displacement.

14. In an expansive reamer, the combination of a body having a cam surface at its upper end; a cutter rod extending axially of the body and supported thereon for` longitudinal movement in relation to said body, a roller cutter on said rod rotatable with said rod as its axis and extending substantially vertical, the upper end of said rod bearing on. said cam surface; an expander upon which the lower end of said lrod is loosely seated allowing pivotal movement of said rod to enable tilting movement of the latter, said expander being slidable longitudinally in relation to said body, resilient means pressing said expander upwardly in relation to said body, said cam surface directing the upper end of said rod outwardly and upwardly whereby said rod is tilted outwardly to expanded position.

15. In an expansive roller reamer, the combination of a body; a cutter carrier extending axially of the body and supported thereon for longitudinal movement in relation to said body, a roller journalled on said carrier with its axis of rotation extending lengthwise of the drilling axis of said body; mounting means upon which one end of said carrier is loosely seated allowing longitudinal movement of the carrier, enabling tilting, movement of the carrier at the other end and including resilient means urging said carrier toward the other end; and coacting means on the body and carrier at said other end to cause outward tilting movement of said carrier by virtue of its longitudinal movement toward said other end comprising a longitudinal extension on said carrier and a socket for said extension with coacting guide surfaces on said extension and body to direct said carrier outward at said other end to a position with said extension andr socket alinedjone of said guide surfaces extending diagonally toward sald socket. v

16. In an expansive roller reamer, the combination of a body; a cutter carrier extending axially of the body and supported thereon'for longitudinalv movement in relation to said body, a roller journalled on said carrier with its axis of rotation extending lengthwise of the drilling axis of said body; an expander upon which one end of said carrier isy loosely seated, enabling tilting movement of the carrier at the other end, said expander being slidably mounted in relation to said body, resilient means urging said expander toward said other end; and coacting means on the body and carrier at said other end to cause outward tilting movement of said carrier by virtue of its longitudinal movement toward said other end comprising alongitudinal extension on said carrier and a recess in said body for said extension, there being a cam surface on said body against which the end of said extension bears to direct said carrier outward at said other end to a. position. withsaid extension and recess in registration, said cam surface extending diagonally toward said recess.

., 17. In an expansive roller reanier, the combination of a body, a cutter rod extending axially of the body and supported thereon for longitudinal movement in relation to said body, a roller journalled on said carrier l. with its axis of rotation extending lengthwise of the drilling axis of said body; an expander upon which one end of said .rod is loosely seated enabling tilting movement of said rod at the other end, said expander being longitudinally slidable in relation to said body, resilient means urging said expander toward the other end; and coactingnieans 0n the body and carrier at said other end to cause outward tilting movement of said carrier by virtue of its longitudinal movement toward said other end comprising a socket for the other end of said rod, a cam surface on said body against which the end of said rod bears to direct said rod outward to a position with said other end of said rod and socket in alinement, said cam surface extendiner diagonally toward said socket.

18. n an expansive roller reamer, the combination of a body having an external cutter cove; a cutter carrier rod extending lengthwise of the body, positioned in said cove and supported on said body for longitudinal movement in relation to said body, a roller cutter on said carrier rotatable with said rod as its axis; mounting means upon which one end of said rod is loosely seated enabling tilting movement of said rod at the other end, and means supported from said .body at said end urging said rod toward the other end; and coacting mea-ns on the body and rod at said other end to cause outward tilting movement of said rod by virtue of its longitudinal with said extension and socket in alinement,

one of said guide surfaces extending diagonally toward said socket.

19. In an expansive roller reamer, the combination of a body having an external cutter cove; a cutter carrier extending lengthwise of the body and positioned in said cove and supported on said body for longitudinal movement in relation to said body, a roller cutter journalled on said carrier with its axis of rotation extending lengthwise of the drilling axis of said body; mounting means upon which one end of said carrier is loosely seated allowing longitudinal movement of the carrier and enabling tilting movement of the carrier at the other end, and resilient means supported from said body at said end urging said carrier toward the other end; and coacting means on the body and carrier at said other end to cause outward tilting movement of said carrier by virtue of its longitudinal movement toward said other end comprising a longitudinal pin extension on said carrier, a socket for said pin extension and a coacting cam surface on body against which said pin extension bears to direct said carrier outward to position with said pin extension and socket in registration, said cam surface extending diagonally toward said socket.

20. In an expansive roller reamer, the combination of a body having an external cutter cove; a cutter carrier extending lengthwise of the body positioned in said cove and supported on said body for longitudinal movement in relation to said body, a roller cutter journalled on said carrier with its axis of rotation ext-ending lengthwise of the drilling axis of said body; an expander upon which one end of said carrier is loosely seated allowing tilting movement of the carrier at the other end, said expander being longitudinally sldable in relation to said body, resilient means supported from said body urging said expander toward the other end; and coacting means on the body and carrier at said other end to cause outward tilting movement of said carrier by virtue of its longitudinal movement toward said other end comprising a longitudinal pin extension on said carrier, a socket in said body for said pin extension and a coacting cam surface on said body extending diagonally toward said socket to directsaid carrier outward to position with said pin extension and socket in alinement.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 16th day of November, 1927. y

" GROVER C. DEAKIN S. 

